Electronic instruments which non-invasively measure biophysical characteristics of the skin, such as moisture level, are used to evaluate cosmetics, personal care products and pharmaceuticals, for example. Additionally, they are used in clinical studies and medical research typically involving a number of subjects.
These electronic instruments use skin testing probes which have permanently attached sensors that are actually physically contacted with each subject's skin. The electronic instruments and skin testing probes are available, for example, from NOVA Technology Corporation, Gloucester, Mass.; I.B.S. Co., Ltd., Japan; and Courage & Khazaka Gmbh, Koln, Germany. The device sold by NOVA allows the probes to be disconnected from the electronic instrument; however, the two foreign manufacturers' probes are hardwired to their electronic instruments.
After each use with a particular subject, especially when used to evaluate wounds or genital areas of the body, a new probe or a sterilized probe must be used to prevent the transmission of contagious diseases from one subject to another. Because the probes are relatively expensive, costing approximately $500 to over $700 a piece, it is generally not economically feasible to keep on hand a large number of probes, thus, a small number of probes must be used which must be sterilized often, especially when there a large number of subjects. This results in a costly and time consuming process both for the users of the probes and their subjects. It is even more difficult when the probes are hardwired to the electronic instruments.
Another problem is that if a different size sensor is desired there must be used either an entirely new probe, in the case of the NOVA device, or an entirely new measurement device, in the case of the German and Japanese devices.